/*
- * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2004-2012 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/sysctl.h>
+#include <sys/mcache.h>
+#include <sys/protosw.h>
#include <string.h>
#include <net/if_arp.h>
#include <net/if_dl.h>
#include <net/dlil.h>
+#include <net/if_types.h>
+#include <net/if_llreach.h>
#include <net/route.h>
#include <netinet/if_ether.h>
#include <netinet/in_var.h>
+#include <kern/zalloc.h>
-#define SIN(s) ((struct sockaddr_in *)s)
#define CONST_LLADDR(s) ((const u_char*)((s)->sdl_data + (s)->sdl_nlen))
-#define rt_expire rt_rmx.rmx_expire
+#define equal(a1, a2) (bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0)
static const size_t MAX_HW_LEN = 10;
SYSCTL_DECL(_net_link_ether);
-SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
+SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW|CTLFLAG_LOCKED, 0, "");
/* timer values */
static int arpt_prune = (5*60*1); /* walk list every 5 minutes */
int apple_hwcksum_tx = 1;
int apple_hwcksum_rx = 1;
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl, CTLFLAG_RW,
- &arpt_prune, 0, "");
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_RW,
- &arpt_keep, 0, "");
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time, CTLFLAG_RW,
- &arpt_down, 0, "");
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, apple_hwcksum_tx, CTLFLAG_RW,
- &apple_hwcksum_tx, 0, "");
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, apple_hwcksum_rx, CTLFLAG_RW,
- &apple_hwcksum_rx, 0, "");
+static int arp_llreach_base = (LL_BASE_REACHABLE / 1000); /* seconds */
+
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, prune_intvl,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &arpt_prune, 0, "");
+
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &arpt_keep, 0, "");
+
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, host_down_time,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &arpt_down, 0, "");
+
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, apple_hwcksum_tx,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &apple_hwcksum_tx, 0, "");
+
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, apple_hwcksum_rx,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &apple_hwcksum_rx, 0, "");
+
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, arp_llreach_base,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &arp_llreach_base, LL_BASE_REACHABLE,
+ "default ARP link-layer reachability max lifetime (in seconds)");
struct llinfo_arp {
+ /*
+ * The following are protected by rnh_lock
+ */
LIST_ENTRY(llinfo_arp) la_le;
struct rtentry *la_rt;
+ /*
+ * The following are protected by rt_lock
+ */
struct mbuf *la_hold; /* last packet until resolved/timeout */
- long la_asked; /* last time we QUERIED for this addr */
+ struct if_llreach *la_llreach; /* link-layer reachability record */
+ u_int64_t la_lastused; /* last used timestamp */
+ u_int32_t la_asked; /* # of requests sent */
+ u_int32_t la_persist; /* expirable, but stays around */
};
+/*
+ * Synchronization notes:
+ *
+ * The global list of ARP entries are stored in llinfo_arp; an entry
+ * gets inserted into the list when the route is created and gets
+ * removed from the list when it is deleted; this is done as part
+ * of RTM_ADD/RTM_RESOLVE/RTM_DELETE in arp_rtrequest().
+ *
+ * Because rnh_lock and rt_lock for the entry are held during those
+ * operations, the same locks (and thus lock ordering) must be used
+ * elsewhere to access the relevant data structure fields:
+ *
+ * la_le.{le_next,le_prev}, la_rt
+ *
+ * - Routing lock (rnh_lock)
+ *
+ * la_hold, la_asked, la_llreach, la_lastused
+ *
+ * - Routing entry lock (rt_lock)
+ *
+ * Due to the dependency on rt_lock, llinfo_arp has the same lifetime
+ * as the route entry itself. When a route is deleted (RTM_DELETE),
+ * it is simply removed from the global list but the memory is not
+ * freed until the route itself is freed.
+ */
static LIST_HEAD(, llinfo_arp) llinfo_arp;
static int arp_inuse, arp_allocated;
-static int arp_maxtries = 5;
+static u_int32_t arp_maxtries = 5;
static int useloopback = 1; /* use loopback interface for local traffic */
static int arp_proxyall = 0;
+static int arp_sendllconflict = 0;
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW | CTLFLAG_LOCKED,
&arp_maxtries, 0, "");
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW,
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW | CTLFLAG_LOCKED,
&useloopback, 0, "");
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW | CTLFLAG_LOCKED,
&arp_proxyall, 0, "");
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, sendllconflict, CTLFLAG_RW | CTLFLAG_LOCKED,
+ &arp_sendllconflict, 0, "");
-static int log_arp_warnings = 0;
+static int log_arp_warnings = 0; /* Thread safe: no accumulated state */
-SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_warnings, CTLFLAG_RW,
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_warnings,
+ CTLFLAG_RW | CTLFLAG_LOCKED,
&log_arp_warnings, 0,
"log arp warning messages");
+static int keep_announcements = 1; /* Thread safe: no aging of state */
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, keep_announcements,
+ CTLFLAG_RW | CTLFLAG_LOCKED,
+ &keep_announcements, 0,
+ "keep arp announcements");
+
+static int send_conflicting_probes = 1; /* Thread safe: no accumulated state */
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, send_conflicting_probes,
+ CTLFLAG_RW | CTLFLAG_LOCKED,
+ &send_conflicting_probes, 0,
+ "send conflicting link-local arp probes");
+
+static errno_t arp_lookup_route(const struct in_addr *, int,
+ int, route_t *, unsigned int);
+static void arptimer(void *);
+static struct llinfo_arp *arp_llinfo_alloc(void);
+static void arp_llinfo_free(void *);
+static void arp_llinfo_purge(struct rtentry *);
+static void arp_llinfo_get_ri(struct rtentry *, struct rt_reach_info *);
+static void arp_llinfo_get_iflri(struct rtentry *, struct ifnet_llreach_info *);
+
+static __inline void arp_llreach_use(struct llinfo_arp *);
+static __inline int arp_llreach_reachable(struct llinfo_arp *);
+static void arp_llreach_alloc(struct rtentry *, struct ifnet *, void *,
+ unsigned int, boolean_t);
+
extern u_int32_t ipv4_ll_arp_aware;
+static int arpinit_done;
+
+static struct zone *llinfo_arp_zone;
+#define LLINFO_ARP_ZONE_MAX 256 /* maximum elements in zone */
+#define LLINFO_ARP_ZONE_NAME "llinfo_arp" /* name for zone */
+
+void
+arp_init(void)
+{
+ if (arpinit_done) {
+ log(LOG_NOTICE, "arp_init called more than once (ignored)\n");
+ return;
+ }
+
+ LIST_INIT(&llinfo_arp);
+
+ llinfo_arp_zone = zinit(sizeof (struct llinfo_arp),
+ LLINFO_ARP_ZONE_MAX * sizeof (struct llinfo_arp), 0,
+ LLINFO_ARP_ZONE_NAME);
+ if (llinfo_arp_zone == NULL)
+ panic("%s: failed allocating llinfo_arp_zone", __func__);
+
+ zone_change(llinfo_arp_zone, Z_EXPAND, TRUE);
+ zone_change(llinfo_arp_zone, Z_CALLERACCT, FALSE);
+
+ arpinit_done = 1;
+
+ /* start timer */
+ timeout(arptimer, (caddr_t)0, hz);
+}
+
+static struct llinfo_arp *
+arp_llinfo_alloc(void)
+{
+ return (zalloc(llinfo_arp_zone));
+}
+
+static void
+arp_llinfo_free(void *arg)
+{
+ struct llinfo_arp *la = arg;
+
+ if (la->la_le.le_next != NULL || la->la_le.le_prev != NULL) {
+ panic("%s: trying to free %p when it is in use", __func__, la);
+ /* NOTREACHED */
+ }
+
+ /* Just in case there's anything there, free it */
+ if (la->la_hold != NULL) {
+ m_freem(la->la_hold);
+ la->la_hold = NULL;
+ }
+
+ /* Purge any link-layer info caching */
+ VERIFY(la->la_rt->rt_llinfo == la);
+ if (la->la_rt->rt_llinfo_purge != NULL)
+ la->la_rt->rt_llinfo_purge(la->la_rt);
+
+ zfree(llinfo_arp_zone, la);
+}
+
+static void
+arp_llinfo_purge(struct rtentry *rt)
+{
+ struct llinfo_arp *la = rt->rt_llinfo;
+
+ RT_LOCK_ASSERT_HELD(rt);
+ VERIFY(rt->rt_llinfo_purge == arp_llinfo_purge && la != NULL);
+
+ if (la->la_llreach != NULL) {
+ RT_CONVERT_LOCK(rt);
+ ifnet_llreach_free(la->la_llreach);
+ la->la_llreach = NULL;
+ }
+ la->la_lastused = 0;
+}
+
+static void
+arp_llinfo_get_ri(struct rtentry *rt, struct rt_reach_info *ri)
+{
+ struct llinfo_arp *la = rt->rt_llinfo;
+ struct if_llreach *lr = la->la_llreach;
+
+ if (lr == NULL) {
+ bzero(ri, sizeof (*ri));
+ ri->ri_rssi = IFNET_RSSI_UNKNOWN;
+ ri->ri_lqm = IFNET_LQM_THRESH_OFF;
+ ri->ri_npm = IFNET_NPM_THRESH_UNKNOWN;
+ } else {
+ IFLR_LOCK(lr);
+ /* Export to rt_reach_info structure */
+ ifnet_lr2ri(lr, ri);
+ /* Export ARP send expiration (calendar) time */
+ ri->ri_snd_expire =
+ ifnet_llreach_up2calexp(lr, la->la_lastused);
+ IFLR_UNLOCK(lr);
+ }
+}
+
+static void
+arp_llinfo_get_iflri(struct rtentry *rt, struct ifnet_llreach_info *iflri)
+{
+ struct llinfo_arp *la = rt->rt_llinfo;
+ struct if_llreach *lr = la->la_llreach;
+
+ if (lr == NULL) {
+ bzero(iflri, sizeof (*iflri));
+ iflri->iflri_rssi = IFNET_RSSI_UNKNOWN;
+ iflri->iflri_lqm = IFNET_LQM_THRESH_OFF;
+ iflri->iflri_npm = IFNET_NPM_THRESH_UNKNOWN;
+ } else {
+ IFLR_LOCK(lr);
+ /* Export to ifnet_llreach_info structure */
+ ifnet_lr2iflri(lr, iflri);
+ /* Export ARP send expiration (uptime) time */
+ iflri->iflri_snd_expire =
+ ifnet_llreach_up2upexp(lr, la->la_lastused);
+ IFLR_UNLOCK(lr);
+ }
+}
+
+void
+arp_llreach_set_reachable(struct ifnet *ifp, void *addr, unsigned int alen)
+{
+ /* Nothing more to do if it's disabled */
+ if (arp_llreach_base == 0)
+ return;
+
+ ifnet_llreach_set_reachable(ifp, ETHERTYPE_IP, addr, alen);
+}
+
+static __inline void
+arp_llreach_use(struct llinfo_arp *la)
+{
+ if (la->la_llreach != NULL)
+ la->la_lastused = net_uptime();
+}
+
+static __inline int
+arp_llreach_reachable(struct llinfo_arp *la)
+{
+ struct if_llreach *lr;
+ const char *why = NULL;
+
+ /* Nothing more to do if it's disabled; pretend it's reachable */
+ if (arp_llreach_base == 0)
+ return (1);
+
+ if ((lr = la->la_llreach) == NULL) {
+ /*
+ * Link-layer reachability record isn't present for this
+ * ARP entry; pretend it's reachable and use it as is.
+ */
+ return (1);
+ } else if (ifnet_llreach_reachable(lr)) {
+ /*
+ * Record is present, it's not shared with other ARP
+ * entries and a packet has recently been received
+ * from the remote host; consider it reachable.
+ */
+ if (lr->lr_reqcnt == 1)
+ return (1);
+
+ /* Prime it up, if this is the first time */
+ if (la->la_lastused == 0) {
+ VERIFY(la->la_llreach != NULL);
+ arp_llreach_use(la);
+ }
+
+ /*
+ * Record is present and shared with one or more ARP
+ * entries, and a packet has recently been received
+ * from the remote host. Since it's shared by more
+ * than one IP addresses, we can't rely on the link-
+ * layer reachability alone; consider it reachable if
+ * this ARP entry has been used "recently."
+ */
+ if (ifnet_llreach_reachable_delta(lr, la->la_lastused))
+ return (1);
+
+ why = "has alias(es) and hasn't been used in a while";
+ } else {
+ why = "haven't heard from it in a while";
+ }
+
+ if (log_arp_warnings) {
+ char tmp[MAX_IPv4_STR_LEN];
+ u_int64_t now = net_uptime();
+
+ log(LOG_DEBUG, "%s%d: ARP probe(s) needed for %s; "
+ "%s [lastused %lld, lastrcvd %lld] secs ago\n",
+ lr->lr_ifp->if_name, lr->lr_ifp->if_unit, inet_ntop(AF_INET,
+ &SIN(rt_key(la->la_rt))->sin_addr, tmp, sizeof (tmp)), why,
+ (la->la_lastused ? (int64_t)(now - la->la_lastused) : -1),
+ (lr->lr_lastrcvd ? (int64_t)(now - lr->lr_lastrcvd) : -1));
+
+ }
+ return (0);
+}
+
+/*
+ * Obtain a link-layer source cache entry for the sender.
+ *
+ * NOTE: This is currently only for ARP/Ethernet.
+ */
+static void
+arp_llreach_alloc(struct rtentry *rt, struct ifnet *ifp, void *addr,
+ unsigned int alen, boolean_t solicited)
+{
+ VERIFY(rt->rt_expire == 0 || rt->rt_rmx.rmx_expire != 0);
+ VERIFY(rt->rt_expire != 0 || rt->rt_rmx.rmx_expire == 0);
+ if (arp_llreach_base != 0 &&
+ rt->rt_expire != 0 && rt->rt_ifp != lo_ifp &&
+ ifp->if_addrlen == IF_LLREACH_MAXLEN && /* Ethernet */
+ alen == ifp->if_addrlen) {
+ struct llinfo_arp *la = rt->rt_llinfo;
+ struct if_llreach *lr;
+ const char *why = NULL, *type = "";
+
+ /* Become a regular mutex, just in case */
+ RT_CONVERT_LOCK(rt);
+
+ if ((lr = la->la_llreach) != NULL) {
+ type = (solicited ? "ARP reply" : "ARP announcement");
+ /*
+ * If target has changed, create a new record;
+ * otherwise keep existing record.
+ */
+ IFLR_LOCK(lr);
+ if (bcmp(addr, lr->lr_key.addr, alen) != 0) {
+ IFLR_UNLOCK(lr);
+ /* Purge any link-layer info caching */
+ VERIFY(rt->rt_llinfo_purge != NULL);
+ rt->rt_llinfo_purge(rt);
+ lr = NULL;
+ why = " for different target HW address; "
+ "using new llreach record";
+ } else {
+ lr->lr_probes = 0; /* reset probe count */
+ IFLR_UNLOCK(lr);
+ if (solicited) {
+ why = " for same target HW address; "
+ "keeping existing llreach record";
+ }
+ }
+ }
+
+ if (lr == NULL) {
+ lr = la->la_llreach = ifnet_llreach_alloc(ifp,
+ ETHERTYPE_IP, addr, alen, arp_llreach_base);
+ if (lr != NULL) {
+ lr->lr_probes = 0; /* reset probe count */
+ if (why == NULL)
+ why = "creating new llreach record";
+ }
+ }
+
+ if (log_arp_warnings && lr != NULL && why != NULL) {
+ char tmp[MAX_IPv4_STR_LEN];
+
+ log(LOG_DEBUG, "%s%d: %s%s for %s\n", ifp->if_name,
+ ifp->if_unit, type, why, inet_ntop(AF_INET,
+ &SIN(rt_key(rt))->sin_addr, tmp, sizeof (tmp)));
+ }
+ }
+}
+
/*
* Free an arp entry.
*/
static void
-arptfree(
- struct llinfo_arp *la)
+arptfree(struct llinfo_arp *la)
{
struct rtentry *rt = la->la_rt;
struct sockaddr_dl *sdl;
- lck_mtx_assert(rt_mtx, LCK_MTX_ASSERT_OWNED);
- if (rt == 0)
- panic("arptfree");
+
+ lck_mtx_assert(rnh_lock, LCK_MTX_ASSERT_OWNED);
+ RT_LOCK_ASSERT_HELD(rt);
+
if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
sdl->sdl_family == AF_LINK) {
sdl->sdl_alen = 0;
la->la_asked = 0;
rt->rt_flags &= ~RTF_REJECT;
- return;
+ RT_UNLOCK(rt);
+ } else if (la->la_persist) {
+ /*
+ * Instead of issuing RTM_DELETE, stop this route entry
+ * from holding an interface idle reference count; if
+ * the route is later reused, arp_validate() will revert
+ * this action.
+ */
+ if (rt->rt_refcnt == 0)
+ rt_clear_idleref(rt);
+ RT_UNLOCK(rt);
+ } else {
+ /*
+ * Safe to drop rt_lock and use rt_key, since holding
+ * rnh_lock here prevents another thread from calling
+ * rt_setgate() on this route.
+ */
+ RT_UNLOCK(rt);
+ rtrequest_locked(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt),
+ 0, NULL);
}
- rtrequest_locked(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, rt_mask(rt),
- 0, (struct rtentry **)0);
}
-/*
- * Timeout routine. Age arp_tab entries periodically.
- */
-/* ARGSUSED */
-static void
-arptimer(
- __unused void *ignored_arg)
+void
+in_arpdrain(void *ignored_arg)
{
+#pragma unused (ignored_arg)
struct llinfo_arp *la, *ola;
- struct timeval timenow;
+ uint64_t timenow;
- lck_mtx_lock(rt_mtx);
+ lck_mtx_lock(rnh_lock);
la = llinfo_arp.lh_first;
- getmicrotime(&timenow);
+ timenow = net_uptime();
while ((ola = la) != 0) {
struct rtentry *rt = la->la_rt;
la = la->la_le.le_next;
- if (rt->rt_expire && rt->rt_expire <= timenow.tv_sec)
+ RT_LOCK(rt);
+ VERIFY(rt->rt_expire == 0 || rt->rt_rmx.rmx_expire != 0);
+ VERIFY(rt->rt_expire != 0 || rt->rt_rmx.rmx_expire == 0);
+ if (rt->rt_expire && rt->rt_expire <= timenow)
arptfree(ola); /* timer has expired, clear */
+ else
+ RT_UNLOCK(rt);
}
- lck_mtx_unlock(rt_mtx);
+ lck_mtx_unlock(rnh_lock);
+}
+
+void
+arp_validate(struct rtentry *rt)
+{
+ struct llinfo_arp *la = rt->rt_llinfo;
+
+ RT_LOCK_ASSERT_HELD(rt);
+ /*
+ * If this is a persistent ARP entry, make it count towards the
+ * interface idleness just like before arptfree() was called.
+ */
+ if (la->la_persist)
+ rt_set_idleref(rt);
+}
+
+/*
+ * Timeout routine. Age arp_tab entries periodically.
+ */
+/* ARGSUSED */
+static void
+arptimer(void *ignored_arg)
+{
+#pragma unused (ignored_arg)
+ in_arpdrain(NULL);
timeout(arptimer, (caddr_t)0, arpt_prune * hz);
}
__unused struct sockaddr *sa)
{
struct sockaddr *gate = rt->rt_gateway;
- struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
+ struct llinfo_arp *la = rt->rt_llinfo;
static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK, 0, 0, 0, 0, 0, {0}};
- static int arpinit_done;
- struct timeval timenow;
+ uint64_t timenow;
if (!arpinit_done) {
- arpinit_done = 1;
- LIST_INIT(&llinfo_arp);
- timeout(arptimer, (caddr_t)0, hz);
+ panic("%s: ARP has not been initialized", __func__);
+ /* NOTREACHED */
}
- lck_mtx_assert(rt_mtx, LCK_MTX_ASSERT_OWNED);
+ lck_mtx_assert(rnh_lock, LCK_MTX_ASSERT_OWNED);
+ RT_LOCK_ASSERT_HELD(rt);
if (rt->rt_flags & RTF_GATEWAY)
return;
- getmicrotime(&timenow);
+ timenow = net_uptime();
switch (req) {
case RTM_ADD:
* such as older version of routed or gated might provide,
* restore cloning bit.
*/
- if ((rt->rt_flags & RTF_HOST) == 0 &&
+ if ((rt->rt_flags & RTF_HOST) == 0 && rt_mask(rt) != NULL &&
SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
rt->rt_flags |= RTF_CLONING;
if (rt->rt_flags & RTF_CLONING) {
/*
* Case 1: This route should come from a route to iface.
*/
- rt_setgate(rt, rt_key(rt),
- (struct sockaddr *)&null_sdl);
- gate = rt->rt_gateway;
- SDL(gate)->sdl_type = rt->rt_ifp->if_type;
- SDL(gate)->sdl_index = rt->rt_ifp->if_index;
- rt->rt_expire = timenow.tv_sec;
+ if (rt_setgate(rt, rt_key(rt),
+ (struct sockaddr *)&null_sdl) == 0) {
+ gate = rt->rt_gateway;
+ SDL(gate)->sdl_type = rt->rt_ifp->if_type;
+ SDL(gate)->sdl_index = rt->rt_ifp->if_index;
+ /*
+ * In case we're called before 1.0 sec.
+ * has elapsed.
+ */
+ rt_setexpire(rt, MAX(timenow, 1));
+ }
break;
}
/* Announce a new entry if requested. */
- if (rt->rt_flags & RTF_ANNOUNCE)
- dlil_send_arp(rt->rt_ifp, ARPOP_REQUEST, SDL(gate), rt_key(rt), (struct sockaddr_dl *)rt_key(rt), NULL);
+ if (rt->rt_flags & RTF_ANNOUNCE) {
+ if (la != NULL)
+ arp_llreach_use(la); /* Mark use timestamp */
+ RT_UNLOCK(rt);
+ dlil_send_arp(rt->rt_ifp, ARPOP_REQUEST,
+ SDL(gate), rt_key(rt), NULL, rt_key(rt), 0);
+ RT_LOCK(rt);
+ }
/*FALLTHROUGH*/
case RTM_RESOLVE:
if (gate->sa_family != AF_LINK ||
gate->sa_len < sizeof(null_sdl)) {
- if (log_arp_warnings)
+ if (log_arp_warnings)
log(LOG_DEBUG, "arp_rtrequest: bad gateway value\n");
break;
}
* Case 2: This route may come from cloning, or a manual route
* add with a LL address.
*/
- R_Malloc(la, struct llinfo_arp *, sizeof(*la));
- rt->rt_llinfo = (caddr_t)la;
- if (la == 0) {
- if ( log_arp_warnings)
- log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
+ rt->rt_llinfo = la = arp_llinfo_alloc();
+ if (la == NULL) {
+ if (log_arp_warnings)
+ log(LOG_DEBUG, "%s: malloc failed\n", __func__);
break;
}
+ rt->rt_llinfo_get_ri = arp_llinfo_get_ri;
+ rt->rt_llinfo_get_iflri = arp_llinfo_get_iflri;
+ rt->rt_llinfo_purge = arp_llinfo_purge;
+ rt->rt_llinfo_free = arp_llinfo_free;
+
arp_inuse++, arp_allocated++;
Bzero(la, sizeof(*la));
la->la_rt = rt;
rt->rt_flags |= RTF_LLINFO;
LIST_INSERT_HEAD(&llinfo_arp, la, la_le);
-#if INET
/*
* This keeps the multicast addresses from showing up
* in `arp -a' listings as unresolved. It's not actually
- * functional. Then the same for broadcast.
+ * functional. Then the same for broadcast. For IPv4
+ * link-local address, keep the entry around even after
+ * it has expired.
*/
if (IN_MULTICAST(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {
- dlil_resolve_multi(rt->rt_ifp, rt_key(rt), gate, sizeof(struct sockaddr_dl));
- rt->rt_expire = 0;
+ RT_UNLOCK(rt);
+ dlil_resolve_multi(rt->rt_ifp, rt_key(rt), gate,
+ sizeof(struct sockaddr_dl));
+ RT_LOCK(rt);
+ rt_setexpire(rt, 0);
}
else if (in_broadcast(SIN(rt_key(rt))->sin_addr, rt->rt_ifp)) {
struct sockaddr_dl *gate_ll = SDL(gate);
size_t broadcast_len;
- ifnet_llbroadcast_copy_bytes(rt->rt_ifp, LLADDR(gate_ll),
- sizeof(gate_ll->sdl_data),
- &broadcast_len);
+ ifnet_llbroadcast_copy_bytes(rt->rt_ifp,
+ LLADDR(gate_ll), sizeof(gate_ll->sdl_data),
+ &broadcast_len);
gate_ll->sdl_alen = broadcast_len;
gate_ll->sdl_family = AF_LINK;
gate_ll->sdl_len = sizeof(struct sockaddr_dl);
- rt->rt_expire = timenow.tv_sec;
+ /* In case we're called before 1.0 sec. has elapsed */
+ rt_setexpire(rt, MAX(timenow, 1));
+ } else if (IN_LINKLOCAL(ntohl(SIN(rt_key(rt))->sin_addr.s_addr))) {
+ /*
+ * The persistent bit implies that once the ARP
+ * entry has reached it expiration time, the idle
+ * reference count to the interface will be released,
+ * but the ARP entry itself stays in the routing table
+ * until it is explicitly removed.
+ */
+ la->la_persist = 1;
+ rt->rt_flags |= RTF_STATIC;
}
-#endif
+ /* Become a regular mutex, just in case */
+ RT_CONVERT_LOCK(rt);
+ IFA_LOCK_SPIN(rt->rt_ifa);
if (SIN(rt_key(rt))->sin_addr.s_addr ==
(IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
- /*
- * This test used to be
- * if (loif.if_flags & IFF_UP)
- * It allowed local traffic to be forced
- * through the hardware by configuring the loopback down.
- * However, it causes problems during network configuration
- * for boards that can't receive packets they send.
- * It is now necessary to clear "useloopback" and remove
- * the route to force traffic out to the hardware.
- */
- rt->rt_expire = 0;
- ifnet_lladdr_copy_bytes(rt->rt_ifp, LLADDR(SDL(gate)), SDL(gate)->sdl_alen = 6);
- if (useloopback)
- rt->rt_ifp = loif;
+ IFA_UNLOCK(rt->rt_ifa);
+ /*
+ * This test used to be
+ * if (loif.if_flags & IFF_UP)
+ * It allowed local traffic to be forced through the
+ * hardware by configuring the loopback down. However,
+ * it causes problems during network configuration
+ * for boards that can't receive packets they send.
+ * It is now necessary to clear "useloopback" and
+ * remove the route to force traffic out to the
+ * hardware.
+ */
+ rt_setexpire(rt, 0);
+ ifnet_lladdr_copy_bytes(rt->rt_ifp, LLADDR(SDL(gate)),
+ SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
+ if (useloopback) {
+ if (rt->rt_ifp != lo_ifp) {
+ /*
+ * Purge any link-layer info caching.
+ */
+ if (rt->rt_llinfo_purge != NULL)
+ rt->rt_llinfo_purge(rt);
+ /*
+ * Adjust route ref count for the
+ * interfaces.
+ */
+ if (rt->rt_if_ref_fn != NULL) {
+ rt->rt_if_ref_fn(lo_ifp, 1);
+ rt->rt_if_ref_fn(rt->rt_ifp, -1);
+ }
+ }
+ rt->rt_ifp = lo_ifp;
+ }
+ } else {
+ IFA_UNLOCK(rt->rt_ifa);
}
break;
if (la == 0)
break;
arp_inuse--;
+ /*
+ * Unchain it but defer the actual freeing until the route
+ * itself is to be freed. rt->rt_llinfo still points to
+ * llinfo_arp, and likewise, la->la_rt still points to this
+ * route entry, except that RTF_LLINFO is now cleared.
+ */
LIST_REMOVE(la, la_le);
- rt->rt_llinfo = 0;
+ la->la_le.le_next = NULL;
+ la->la_le.le_prev = NULL;
+
+ /*
+ * Purge any link-layer info caching.
+ */
+ if (rt->rt_llinfo_purge != NULL)
+ rt->rt_llinfo_purge(rt);
+
rt->rt_flags &= ~RTF_LLINFO;
- if (la->la_hold) {
+ if (la->la_hold != NULL) {
m_freem(la->la_hold);
+ la->la_hold = NULL;
}
- la->la_hold = NULL;
- R_Free((caddr_t)la);
}
}
{
char * buf = orig_buf;
int i;
- const u_char * lladdr = sdl->sdl_data;
+ const u_char * lladdr = (u_char *)(size_t)sdl->sdl_data;
int maxbytes = buflen / 3;
if (maxbytes > sdl->sdl_alen) {
/*
* arp_lookup_route will lookup the route for a given address.
*
- * The routing lock must be held. The address must be for a
- * host on a local network on this interface.
+ * The address must be for a host on a local network on this interface.
+ * If the returned route is non-NULL, the route is locked and the caller
+ * is responsible for unlocking it and releasing its reference.
*/
static errno_t
-arp_lookup_route(
- const struct in_addr *addr,
- int create,
- int proxy,
- route_t *route)
+arp_lookup_route(const struct in_addr *addr, int create, int proxy,
+ route_t *route, unsigned int ifscope)
{
struct sockaddr_inarp sin = {sizeof(sin), AF_INET, 0, {0}, {0}, 0, 0};
- const char *why = 0;
+ const char *why = NULL;
errno_t error = 0;
-
- // Caller is responsible for taking the routing lock
- lck_mtx_assert(rt_mtx, LCK_MTX_ASSERT_OWNED);
+ route_t rt;
+
+ *route = NULL;
sin.sin_addr.s_addr = addr->s_addr;
sin.sin_other = proxy ? SIN_PROXY : 0;
-
- *route = rtalloc1_locked((const struct sockaddr*)&sin, create, 0);
- if (*route == NULL)
- return ENETUNREACH;
-
- rtunref(*route);
-
- if ((*route)->rt_flags & RTF_GATEWAY) {
+
+ /*
+ * If the destination is a link-local address, don't
+ * constrain the lookup (don't scope it).
+ */
+ if (IN_LINKLOCAL(ntohl(addr->s_addr)))
+ ifscope = IFSCOPE_NONE;
+
+ rt = rtalloc1_scoped((struct sockaddr*)&sin, create, 0, ifscope);
+ if (rt == NULL)
+ return (ENETUNREACH);
+
+ RT_LOCK(rt);
+
+ if (rt->rt_flags & RTF_GATEWAY) {
why = "host is not on local network";
-
- /* If there are no references to this route, purge it */
- if ((*route)->rt_refcnt <= 0 && ((*route)->rt_flags & RTF_WASCLONED) != 0) {
- rtrequest_locked(RTM_DELETE,
- (struct sockaddr *)rt_key(*route),
- (*route)->rt_gateway, rt_mask(*route),
- (*route)->rt_flags, 0);
- }
- *route = NULL;
error = ENETUNREACH;
- }
- else if (((*route)->rt_flags & RTF_LLINFO) == 0) {
+ } else if (!(rt->rt_flags & RTF_LLINFO)) {
why = "could not allocate llinfo";
- *route = NULL;
error = ENOMEM;
- }
- else if ((*route)->rt_gateway->sa_family != AF_LINK) {
+ } else if (rt->rt_gateway->sa_family != AF_LINK) {
why = "gateway route is not ours";
- *route = NULL;
error = EPROTONOSUPPORT;
}
-
- if (why && create && log_arp_warnings) {
- char tmp[MAX_IPv4_STR_LEN];
- log(LOG_DEBUG, "arplookup %s failed: %s\n",
- inet_ntop(AF_INET, addr, tmp, sizeof(tmp)), why);
- }
-
- return error;
-}
-
-__private_extern__ errno_t
-arp_route_to_gateway_route(
- const struct sockaddr *net_dest,
- route_t hint,
- route_t *out_route);
-/*
- * arp_route_to_gateway_route will find the gateway route for a given route.
- *
- * If the route is down, look the route up again.
- * If the route goes through a gateway, get the route to the gateway.
- * If the gateway route is down, look it up again.
- * If the route is set to reject, verify it hasn't expired.
- */
-__private_extern__ errno_t
-arp_route_to_gateway_route(
- const struct sockaddr *net_dest,
- route_t hint,
- route_t *out_route)
-{
- route_t route = hint;
- *out_route = NULL;
- struct timeval timenow;
-
- /* If we got a hint from the higher layers, check it out */
- if (route) {
- lck_mtx_lock(rt_mtx);
-
- if ((route->rt_flags & RTF_UP) == 0) {
- /* route is down, find a new one */
- hint = route = rtalloc1_locked(net_dest, 1, 0);
- if (hint) {
- rtunref(hint);
- }
- else {
- /* No route to host */
- lck_mtx_unlock(rt_mtx);
- return EHOSTUNREACH;
- }
+ if (error != 0) {
+ if (create && log_arp_warnings) {
+ char tmp[MAX_IPv4_STR_LEN];
+ log(LOG_DEBUG, "arplookup link#%d %s failed: %s\n",
+ ifscope, inet_ntop(AF_INET, addr, tmp,
+ sizeof (tmp)), why);
}
-
- if (route->rt_flags & RTF_GATEWAY) {
+
+ /*
+ * If there are no references to this route, and it is
+ * a cloned route, and not static, and ARP had created
+ * the route, then purge it from the routing table as
+ * it is probably bogus.
+ */
+ if (rt->rt_refcnt == 1 &&
+ (rt->rt_flags & (RTF_WASCLONED | RTF_STATIC)) ==
+ RTF_WASCLONED) {
/*
- * We need the gateway route. If it is NULL or down,
- * look it up.
+ * Prevent another thread from modiying rt_key,
+ * rt_gateway via rt_setgate() after rt_lock is
+ * dropped by marking the route as defunct.
*/
- if (route->rt_gwroute == 0 ||
- (route->rt_gwroute->rt_flags & RTF_UP) == 0) {
- if (route->rt_gwroute != 0)
- rtfree_locked(route->rt_gwroute);
-
- route->rt_gwroute = rtalloc1_locked(route->rt_gateway, 1, 0);
- if (route->rt_gwroute == 0) {
- lck_mtx_unlock(rt_mtx);
- return EHOSTUNREACH;
- }
- }
-
- route = route->rt_gwroute;
+ rt->rt_flags |= RTF_CONDEMNED;
+ RT_UNLOCK(rt);
+ rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
+ rt_mask(rt), rt->rt_flags, 0);
+ rtfree(rt);
+ } else {
+ RT_REMREF_LOCKED(rt);
+ RT_UNLOCK(rt);
}
-
- if (route->rt_flags & RTF_REJECT) {
- getmicrotime(&timenow);
- if (route->rt_rmx.rmx_expire == 0 ||
- timenow.tv_sec < route->rt_rmx.rmx_expire) {
- lck_mtx_unlock(rt_mtx);
- return route == hint ? EHOSTDOWN : EHOSTUNREACH;
- }
- }
-
- lck_mtx_unlock(rt_mtx);
+ return (error);
}
-
- *out_route = route;
- return 0;
+
+ /*
+ * Caller releases reference and does RT_UNLOCK(rt).
+ */
+ *route = rt;
+ return (0);
}
+/*
+ * This is the ARP pre-output routine; care must be taken to ensure that
+ * the "hint" route never gets freed via rtfree(), since the caller may
+ * have stored it inside a struct route with a reference held for that
+ * placeholder.
+ */
errno_t
-arp_lookup_ip(
- ifnet_t ifp,
- const struct sockaddr_in *net_dest,
- struct sockaddr_dl *ll_dest,
- size_t ll_dest_len,
- route_t hint,
- mbuf_t packet)
+arp_lookup_ip(ifnet_t ifp, const struct sockaddr_in *net_dest,
+ struct sockaddr_dl *ll_dest, size_t ll_dest_len, route_t hint,
+ mbuf_t packet)
{
- route_t route = NULL;
+ route_t route = NULL; /* output route */
errno_t result = 0;
struct sockaddr_dl *gateway;
- struct llinfo_arp *llinfo;
- struct timeval timenow;
-
+ struct llinfo_arp *llinfo = NULL;
+ uint64_t timenow;
+ int unreachable = 0;
+
if (net_dest->sin_family != AF_INET)
- return EAFNOSUPPORT;
-
+ return (EAFNOSUPPORT);
+
if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
- return ENETDOWN;
-
+ return (ENETDOWN);
+
/*
* If we were given a route, verify the route and grab the gateway
*/
- if (hint) {
- result = arp_route_to_gateway_route((const struct sockaddr*)net_dest,
- hint, &route);
+ if (hint != NULL) {
+ /*
+ * Callee holds a reference on the route and returns
+ * with the route entry locked, upon success.
+ */
+ result = route_to_gwroute((const struct sockaddr *)
+ net_dest, hint, &route);
if (result != 0)
- return result;
+ return (result);
+ if (route != NULL)
+ RT_LOCK_ASSERT_HELD(route);
}
-
+
if (packet->m_flags & M_BCAST) {
- u_long broadcast_len;
+ size_t broadcast_len;
bzero(ll_dest, ll_dest_len);
- result = ifnet_llbroadcast_copy_bytes(ifp, LLADDR(ll_dest), ll_dest_len
- - offsetof(struct sockaddr_dl,
- sdl_data), &broadcast_len);
- if (result != 0) {
- return result;
+ result = ifnet_llbroadcast_copy_bytes(ifp, LLADDR(ll_dest),
+ ll_dest_len - offsetof(struct sockaddr_dl, sdl_data),
+ &broadcast_len);
+ if (result == 0) {
+ ll_dest->sdl_alen = broadcast_len;
+ ll_dest->sdl_family = AF_LINK;
+ ll_dest->sdl_len = sizeof(struct sockaddr_dl);
}
-
- ll_dest->sdl_alen = broadcast_len;
- ll_dest->sdl_family = AF_LINK;
- ll_dest->sdl_len = sizeof(struct sockaddr_dl);
-
- return 0;
+ goto release;
}
if (packet->m_flags & M_MCAST) {
- return dlil_resolve_multi(ifp, (const struct sockaddr*)net_dest,
- (struct sockaddr*)ll_dest, ll_dest_len);
+ if (route != NULL)
+ RT_UNLOCK(route);
+ result = dlil_resolve_multi(ifp,
+ (const struct sockaddr*)net_dest,
+ (struct sockaddr*)ll_dest, ll_dest_len);
+ if (route != NULL)
+ RT_LOCK(route);
+ goto release;
}
-
- lck_mtx_lock(rt_mtx);
-
+
/*
* If we didn't find a route, or the route doesn't have
* link layer information, trigger the creation of the
* route and link layer information.
*/
- if (route == NULL || route->rt_llinfo == NULL)
- result = arp_lookup_route(&net_dest->sin_addr, 1, 0, &route);
-
- if (result || route == NULL || route->rt_llinfo == NULL) {
+ if (route == NULL || route->rt_llinfo == NULL) {
+ /* Clean up now while we can */
+ if (route != NULL) {
+ if (route == hint) {
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
+ } else {
+ RT_UNLOCK(route);
+ rtfree(route);
+ }
+ }
+ /*
+ * Callee holds a reference on the route and returns
+ * with the route entry locked, upon success.
+ */
+ result = arp_lookup_route(&net_dest->sin_addr, 1, 0, &route,
+ ifp->if_index);
+ if (result == 0)
+ RT_LOCK_ASSERT_HELD(route);
+ }
+
+ if (result || route == NULL || (llinfo = route->rt_llinfo) == NULL) {
char tmp[MAX_IPv4_STR_LEN];
- lck_mtx_unlock(rt_mtx);
- if (log_arp_warnings)
- log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s\n",
- inet_ntop(AF_INET, &net_dest->sin_addr, tmp, sizeof(tmp)));
- return result;
+
+ /* In case result is 0 but no route, return an error */
+ if (result == 0)
+ result = EHOSTUNREACH;
+
+ if (log_arp_warnings &&
+ route != NULL && route->rt_llinfo == NULL)
+ log(LOG_DEBUG, "arpresolve: can't allocate llinfo "
+ "for %s\n", inet_ntop(AF_INET, &net_dest->sin_addr,
+ tmp, sizeof(tmp)));
+ goto release;
}
-
+
/*
* Now that we have the right route, is it filled in?
*/
gateway = SDL(route->rt_gateway);
- getmicrotime(&timenow);
- if ((route->rt_rmx.rmx_expire == 0 || route->rt_rmx.rmx_expire > timenow.tv_sec) &&
- gateway != NULL && gateway->sdl_family == AF_LINK && gateway->sdl_alen != 0) {
+ timenow = net_uptime();
+ VERIFY(route->rt_expire == 0 || route->rt_rmx.rmx_expire != 0);
+ VERIFY(route->rt_expire != 0 || route->rt_rmx.rmx_expire == 0);
+ if ((route->rt_expire == 0 ||
+ route->rt_expire > timenow) && gateway != NULL &&
+ gateway->sdl_family == AF_LINK && gateway->sdl_alen != 0 &&
+ !(unreachable = !arp_llreach_reachable(llinfo))) {
bcopy(gateway, ll_dest, MIN(gateway->sdl_len, ll_dest_len));
- lck_mtx_unlock(rt_mtx);
- return 0;
+ result = 0;
+ arp_llreach_use(llinfo); /* Mark use timestamp */
+ goto release;
+ } else if (unreachable) {
+ /*
+ * Discard existing answer in case we need to probe.
+ */
+ gateway->sdl_alen = 0;
}
-
+
+ if (ifp->if_flags & IFF_NOARP) {
+ result = ENOTSUP;
+ goto release;
+ }
+
/*
* Route wasn't complete/valid. We need to arp.
*/
- if (ifp->if_flags & IFF_NOARP) {
- lck_mtx_unlock(rt_mtx);
- return ENOTSUP;
- }
-
- llinfo = (struct llinfo_arp*)route->rt_llinfo;
- if (packet) {
- if (llinfo->la_hold) {
+ if (packet != NULL) {
+ if (llinfo->la_hold != NULL)
m_freem(llinfo->la_hold);
- }
llinfo->la_hold = packet;
}
-
- if (route->rt_rmx.rmx_expire) {
+
+ if (route->rt_expire) {
route->rt_flags &= ~RTF_REJECT;
- if (llinfo->la_asked == 0 || route->rt_rmx.rmx_expire != timenow.tv_sec) {
- route->rt_rmx.rmx_expire = timenow.tv_sec;
+ if (llinfo->la_asked == 0 ||
+ route->rt_expire != timenow) {
+ rt_setexpire(route, timenow);
if (llinfo->la_asked++ < arp_maxtries) {
- lck_mtx_unlock(rt_mtx);
- dlil_send_arp(ifp, ARPOP_REQUEST, NULL, route->rt_ifa->ifa_addr,
- NULL, (const struct sockaddr*)net_dest);
- return EJUSTRETURN;
- }
- else {
+ struct ifaddr *rt_ifa = route->rt_ifa;
+ struct sockaddr *sa;
+ u_int32_t rtflags;
+
+ /* Become a regular mutex, just in case */
+ RT_CONVERT_LOCK(route);
+ /* Update probe count, if applicable */
+ if (llinfo->la_llreach != NULL) {
+ IFLR_LOCK_SPIN(llinfo->la_llreach);
+ llinfo->la_llreach->lr_probes++;
+ IFLR_UNLOCK(llinfo->la_llreach);
+ }
+ IFA_LOCK_SPIN(rt_ifa);
+ IFA_ADDREF_LOCKED(rt_ifa);
+ sa = rt_ifa->ifa_addr;
+ IFA_UNLOCK(rt_ifa);
+ arp_llreach_use(llinfo); /* Mark use timestamp */
+ rtflags = route->rt_flags;
+ RT_UNLOCK(route);
+ dlil_send_arp(ifp, ARPOP_REQUEST, NULL,
+ sa, NULL, (const struct sockaddr*)net_dest,
+ rtflags);
+ IFA_REMREF(rt_ifa);
+ RT_LOCK(route);
+ result = EJUSTRETURN;
+ goto release;
+ } else {
route->rt_flags |= RTF_REJECT;
- route->rt_rmx.rmx_expire += arpt_down;
+ rt_setexpire(route, rt_expiry(route,
+ route->rt_expire, arpt_down));
llinfo->la_asked = 0;
- llinfo->la_hold = 0;
- lck_mtx_unlock(rt_mtx);
- return EHOSTUNREACH;
+ /*
+ * Clear la_hold; don't free the packet since
+ * we're not returning EJUSTRETURN; the caller
+ * will handle the freeing.
+ */
+ llinfo->la_hold = NULL;
+ result = EHOSTUNREACH;
+ goto release;
}
}
}
- lck_mtx_unlock(rt_mtx);
-
- return EJUSTRETURN;
+
+ /* The packet is now held inside la_hold (can "packet" be NULL?) */
+ result = EJUSTRETURN;
+
+release:
+ if (route != NULL) {
+ if (route == hint) {
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
+ } else {
+ RT_UNLOCK(route);
+ rtfree(route);
+ }
+ }
+ return (result);
}
errno_t
const struct sockaddr_in *target_ip)
{
char ipv4str[MAX_IPv4_STR_LEN];
- struct sockaddr_dl *gateway;
+ struct sockaddr_dl proxied;
+ struct sockaddr_dl *gateway, *target_hw = NULL;
+ struct ifaddr *ifa;
struct in_ifaddr *ia;
struct in_ifaddr *best_ia = NULL;
+ struct sockaddr_in best_ia_sin;
route_t route = NULL;
char buf[3 * MAX_HW_LEN]; // enough for MAX_HW_LEN byte hw address
struct llinfo_arp *llinfo;
- struct timeval timenow;
errno_t error;
-
+ int created_announcement = 0;
+ int bridged = 0, is_bridge = 0;
+
/* Do not respond to requests for 0.0.0.0 */
- if (target_ip->sin_addr.s_addr == 0 && arpop == ARPOP_REQUEST) {
- return 0;
- }
-
+ if (target_ip->sin_addr.s_addr == 0 && arpop == ARPOP_REQUEST)
+ goto done;
+
+ if (ifp->if_bridge)
+ bridged = 1;
+ if (ifp->if_type == IFT_BRIDGE)
+ is_bridge = 1;
+
/*
* Determine if this ARP is for us
+ * For a bridge, we want to check the address irrespective
+ * of the receive interface.
*/
- lck_mtx_lock(rt_mtx);
- for (ia = in_ifaddrhead.tqh_first; ia; ia = ia->ia_link.tqe_next) {
- /* do_bridge should be tested here for bridging */
- if (ia->ia_ifp == ifp) {
+ lck_rw_lock_shared(in_ifaddr_rwlock);
+ TAILQ_FOREACH(ia, INADDR_HASH(target_ip->sin_addr.s_addr), ia_hash) {
+ IFA_LOCK_SPIN(&ia->ia_ifa);
+ if (((bridged && ia->ia_ifp->if_bridge != NULL) ||
+ (ia->ia_ifp == ifp)) &&
+ ia->ia_addr.sin_addr.s_addr == target_ip->sin_addr.s_addr) {
best_ia = ia;
- if (target_ip->sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr ||
- sender_ip->sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr) {
- break;
+ best_ia_sin = best_ia->ia_addr;
+ IFA_ADDREF_LOCKED(&ia->ia_ifa);
+ IFA_UNLOCK(&ia->ia_ifa);
+ lck_rw_done(in_ifaddr_rwlock);
+ goto match;
+ }
+ IFA_UNLOCK(&ia->ia_ifa);
+ }
+
+ TAILQ_FOREACH(ia, INADDR_HASH(sender_ip->sin_addr.s_addr), ia_hash) {
+ IFA_LOCK_SPIN(&ia->ia_ifa);
+ if (((bridged && ia->ia_ifp->if_bridge != NULL) ||
+ (ia->ia_ifp == ifp)) &&
+ ia->ia_addr.sin_addr.s_addr == sender_ip->sin_addr.s_addr) {
+ best_ia = ia;
+ best_ia_sin = best_ia->ia_addr;
+ IFA_ADDREF_LOCKED(&ia->ia_ifa);
+ IFA_UNLOCK(&ia->ia_ifa);
+ lck_rw_done(in_ifaddr_rwlock);
+ goto match;
+ }
+ IFA_UNLOCK(&ia->ia_ifa);
+ }
+
+#define BDG_MEMBER_MATCHES_ARP(addr, ifp, ia) \
+ (ia->ia_ifp->if_bridge == ifp->if_softc && \
+ !bcmp(ifnet_lladdr(ia->ia_ifp), ifnet_lladdr(ifp), ifp->if_addrlen) && \
+ addr == ia->ia_addr.sin_addr.s_addr)
+ /*
+ * Check the case when bridge shares its MAC address with
+ * some of its children, so packets are claimed by bridge
+ * itself (bridge_input() does it first), but they are really
+ * meant to be destined to the bridge member.
+ */
+ if (is_bridge) {
+ TAILQ_FOREACH(ia, INADDR_HASH(target_ip->sin_addr.s_addr),
+ ia_hash) {
+ IFA_LOCK_SPIN(&ia->ia_ifa);
+ if (BDG_MEMBER_MATCHES_ARP(target_ip->sin_addr.s_addr,
+ ifp, ia)) {
+ ifp = ia->ia_ifp;
+ best_ia = ia;
+ best_ia_sin = best_ia->ia_addr;
+ IFA_ADDREF_LOCKED(&ia->ia_ifa);
+ IFA_UNLOCK(&ia->ia_ifa);
+ lck_rw_done(in_ifaddr_rwlock);
+ goto match;
}
+ IFA_UNLOCK(&ia->ia_ifa);
}
}
-
- /* If we don't have an IP address on this interface, ignore the packet */
- if (best_ia == 0) {
- lck_mtx_unlock(rt_mtx);
- return 0;
+ lck_rw_done(in_ifaddr_rwlock);
+
+ /*
+ * No match, use the first inet address on the receive interface
+ * as a dummy address for the rest of the function; we may be
+ * proxying for another address.
+ */
+ ifnet_lock_shared(ifp);
+ TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+ IFA_LOCK_SPIN(ifa);
+ if (ifa->ifa_addr->sa_family != AF_INET) {
+ IFA_UNLOCK(ifa);
+ continue;
+ }
+ best_ia = (struct in_ifaddr *)ifa;
+ best_ia_sin = best_ia->ia_addr;
+ IFA_ADDREF_LOCKED(ifa);
+ IFA_UNLOCK(ifa);
+ ifnet_lock_done(ifp);
+ goto match;
}
-
+ ifnet_lock_done(ifp);
+
+ /*
+ * If we're not a bridge member, or if we are but there's no
+ * IPv4 address to use for the interface, drop the packet.
+ */
+ if (!bridged || best_ia == NULL)
+ goto done;
+
+match:
/* If the packet is from this interface, ignore the packet */
- if (!bcmp(CONST_LLADDR(sender_hw), ifnet_lladdr(ifp), sender_hw->sdl_len)) {
- lck_mtx_unlock(rt_mtx);
- return 0;
+ if (!bcmp(CONST_LLADDR(sender_hw), ifnet_lladdr(ifp), sender_hw->sdl_alen)) {
+ goto done;
}
-
+
/* Check for a conflict */
- if (sender_ip->sin_addr.s_addr == best_ia->ia_addr.sin_addr.s_addr) {
+ if (!bridged && sender_ip->sin_addr.s_addr == best_ia_sin.sin_addr.s_addr) {
struct kev_msg ev_msg;
struct kev_in_collision *in_collision;
u_char storage[sizeof(struct kev_in_collision) + MAX_HW_LEN];
- in_collision = (struct kev_in_collision*)storage;
+ bzero(&ev_msg, sizeof(struct kev_msg));
+ bzero(storage, (sizeof(struct kev_in_collision) + MAX_HW_LEN));
+ in_collision = (struct kev_in_collision*)(void *)storage;
log(LOG_ERR, "%s%d duplicate IP address %s sent from address %s\n",
ifp->if_name, ifp->if_unit,
inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str, sizeof(ipv4str)),
sdl_addr_to_hex(sender_hw, buf, sizeof(buf)));
-
+
/* Send a kernel event so anyone can learn of the conflict */
in_collision->link_data.if_family = ifp->if_family;
in_collision->link_data.if_unit = ifp->if_unit;
ev_msg.dv[0].data_length = sizeof(struct kev_in_collision) + in_collision->hw_len;
ev_msg.dv[1].data_length = 0;
kev_post_msg(&ev_msg);
-
+
goto respond;
}
-
+
/*
* Look up the routing entry. If it doesn't exist and we are the
- * target, go ahead and create one.
+ * target, and the sender isn't 0.0.0.0, go ahead and create one.
+ * Callee holds a reference on the route and returns with the route
+ * entry locked, upon success.
*/
- error = arp_lookup_route(&sender_ip->sin_addr, (target_ip->sin_addr.s_addr ==
- best_ia->ia_addr.sin_addr.s_addr), 0, &route);
-
+ error = arp_lookup_route(&sender_ip->sin_addr,
+ (target_ip->sin_addr.s_addr == best_ia_sin.sin_addr.s_addr &&
+ sender_ip->sin_addr.s_addr != 0), 0, &route, ifp->if_index);
+
+ if (error == 0)
+ RT_LOCK_ASSERT_HELD(route);
+
if (error || route == 0 || route->rt_gateway == 0) {
- if (ipv4_ll_arp_aware != 0 && IN_LINKLOCAL(target_ip->sin_addr.s_addr)
- && arpop == ARPOP_REQUEST && sender_ip->sin_addr.s_addr == 0) {
+ if (arpop != ARPOP_REQUEST) {
+ goto respond;
+ }
+ if (arp_sendllconflict
+ && send_conflicting_probes != 0
+ && (ifp->if_eflags & IFEF_ARPLL) != 0
+ && IN_LINKLOCAL(ntohl(target_ip->sin_addr.s_addr))
+ && sender_ip->sin_addr.s_addr == 0) {
/*
* Verify this ARP probe doesn't conflict with an IPv4LL we know of
* on another interface.
*/
- error = arp_lookup_route(&target_ip->sin_addr, 0, 0, &route);
+ if (route != NULL) {
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
+ route = NULL;
+ }
+ /*
+ * Callee holds a reference on the route and returns
+ * with the route entry locked, upon success.
+ */
+ error = arp_lookup_route(&target_ip->sin_addr, 0, 0,
+ &route, ifp->if_index);
+
+ if (error == 0)
+ RT_LOCK_ASSERT_HELD(route);
+
if (error == 0 && route && route->rt_gateway) {
gateway = SDL(route->rt_gateway);
- if (route->rt_ifp != ifp &&
- (gateway->sdl_alen != sender_hw->sdl_alen ||
- bcmp(CONST_LLADDR(gateway), CONST_LLADDR(sender_hw),
- gateway->sdl_alen) != 0)) {
+ if (route->rt_ifp != ifp && gateway->sdl_alen != 0
+ && (gateway->sdl_alen != sender_hw->sdl_alen
+ || bcmp(CONST_LLADDR(gateway), CONST_LLADDR(sender_hw),
+ gateway->sdl_alen) != 0)) {
/*
* A node is probing for an IPv4LL we know exists on a
* different interface. We respond with a conflicting probe
* to force the new device to pick a different IPv4LL
* address.
*/
- log(LOG_INFO,
+ if (log_arp_warnings) {
+ log(LOG_INFO,
"arp: %s on %s%d sent probe for %s, already on %s%d\n",
sdl_addr_to_hex(sender_hw, buf, sizeof(buf)),
ifp->if_name, ifp->if_unit,
inet_ntop(AF_INET, &target_ip->sin_addr, ipv4str,
sizeof(ipv4str)),
route->rt_ifp->if_name, route->rt_ifp->if_unit);
- log(LOG_INFO,
+ log(LOG_INFO,
"arp: sending conflicting probe to %s on %s%d\n",
sdl_addr_to_hex(sender_hw, buf, sizeof(buf)),
ifp->if_name, ifp->if_unit);
-
+ }
+ /* Mark use timestamp */
+ if (route->rt_llinfo != NULL)
+ arp_llreach_use(route->rt_llinfo);
+ /* We're done with the route */
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
+ route = NULL;
/*
* Send a conservative unicast "ARP probe".
* This should force the other device to pick a new number.
* This will not force the device to pick a new number if the device
* has already assigned that number.
* This will not imply to the device that we own that address.
+ * The link address is always present; it's never freed.
*/
+ ifnet_lock_shared(ifp);
+ ifa = ifp->if_lladdr;
+ IFA_ADDREF(ifa);
+ ifnet_lock_done(ifp);
dlil_send_arp_internal(ifp, ARPOP_REQUEST,
- (struct sockaddr_dl*)TAILQ_FIRST(&ifp->if_addrhead)->ifa_addr,
+ SDL(ifa->ifa_addr),
(const struct sockaddr*)sender_ip, sender_hw,
(const struct sockaddr*)target_ip);
- }
+ IFA_REMREF(ifa);
+ ifa = NULL;
+ }
+ }
+ goto respond;
+ } else if (keep_announcements != 0
+ && target_ip->sin_addr.s_addr == sender_ip->sin_addr.s_addr) {
+ /* don't create entry if link-local address and link-local is disabled */
+ if (!IN_LINKLOCAL(ntohl(sender_ip->sin_addr.s_addr))
+ || (ifp->if_eflags & IFEF_ARPLL) != 0) {
+ if (route != NULL) {
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
+ route = NULL;
+ }
+ /*
+ * Callee holds a reference on the route and
+ * returns with the route entry locked, upon
+ * success.
+ */
+ error = arp_lookup_route(&sender_ip->sin_addr,
+ 1, 0, &route, ifp->if_index);
+
+ if (error == 0)
+ RT_LOCK_ASSERT_HELD(route);
+
+ if (error == 0 && route != NULL && route->rt_gateway != NULL) {
+ created_announcement = 1;
+ }
}
+ if (created_announcement == 0) {
+ goto respond;
+ }
+ } else {
+ goto respond;
}
-
- goto respond;
}
-
+
+ RT_LOCK_ASSERT_HELD(route);
+ VERIFY(route->rt_expire == 0 || route->rt_rmx.rmx_expire != 0);
+ VERIFY(route->rt_expire != 0 || route->rt_rmx.rmx_expire == 0);
gateway = SDL(route->rt_gateway);
- if (route->rt_ifp != ifp) {
- if (!IN_LINKLOCAL(sender_ip->sin_addr.s_addr) || (ifp->if_eflags & IFEF_ARPLL) == 0) {
+ if (!bridged && route->rt_ifp != ifp) {
+ if (!IN_LINKLOCAL(ntohl(sender_ip->sin_addr.s_addr)) || (ifp->if_eflags & IFEF_ARPLL) == 0) {
if (log_arp_warnings)
log(LOG_ERR, "arp: %s is on %s%d but got reply from %s on %s%d\n",
inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,
}
else {
/* Don't change a permanent address */
- if (route->rt_rmx.rmx_expire == 0) {
+ if (route->rt_expire == 0) {
goto respond;
}
-
+
+ /*
+ * We're about to check and/or change the route's ifp
+ * and ifa, so do the lock dance: drop rt_lock, hold
+ * rnh_lock and re-hold rt_lock to avoid violating the
+ * lock ordering. We have an extra reference on the
+ * route, so it won't go away while we do this.
+ */
+ RT_UNLOCK(route);
+ lck_mtx_lock(rnh_lock);
+ RT_LOCK(route);
/*
- * Don't change the cloned route away from the parent's interface
- * if the address did resolve.
+ * Don't change the cloned route away from the
+ * parent's interface if the address did resolve
+ * or if the route is defunct. rt_ifp on both
+ * the parent and the clone can now be freely
+ * accessed now that we have acquired rnh_lock.
*/
- if (gateway->sdl_alen != 0 && route->rt_parent &&
- route->rt_parent->rt_ifp == route->rt_ifp) {
+ gateway = SDL(route->rt_gateway);
+ if ((gateway->sdl_alen != 0 && route->rt_parent &&
+ route->rt_parent->rt_ifp == route->rt_ifp) ||
+ (route->rt_flags & RTF_CONDEMNED)) {
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
+ route = NULL;
+ lck_mtx_unlock(rnh_lock);
goto respond;
}
-
+ if (route->rt_ifp != ifp) {
+ /*
+ * Purge any link-layer info caching.
+ */
+ if (route->rt_llinfo_purge != NULL)
+ route->rt_llinfo_purge(route);
+
+ /* Adjust route ref count for the interfaces */
+ if (route->rt_if_ref_fn != NULL) {
+ route->rt_if_ref_fn(ifp, 1);
+ route->rt_if_ref_fn(route->rt_ifp, -1);
+ }
+ }
/* Change the interface when the existing route is on */
route->rt_ifp = ifp;
rtsetifa(route, &best_ia->ia_ifa);
gateway->sdl_index = ifp->if_index;
+ RT_UNLOCK(route);
+ lck_mtx_unlock(rnh_lock);
+ RT_LOCK(route);
+ /* Don't bother if the route is down */
+ if (!(route->rt_flags & RTF_UP))
+ goto respond;
+ /* Refresh gateway pointer */
+ gateway = SDL(route->rt_gateway);
}
+ RT_LOCK_ASSERT_HELD(route);
}
-
+
if (gateway->sdl_alen && bcmp(LLADDR(gateway), CONST_LLADDR(sender_hw), gateway->sdl_alen)) {
- if (route->rt_rmx.rmx_expire) {
+ if (route->rt_expire && log_arp_warnings) {
char buf2[3 * MAX_HW_LEN];
log(LOG_INFO, "arp: %s moved from %s to %s on %s%d\n",
- inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,
- sizeof(ipv4str)),
- sdl_addr_to_hex(gateway, buf, sizeof(buf)),
- sdl_addr_to_hex(sender_hw, buf2, sizeof(buf2)), ifp->if_name,
- ifp->if_unit);
+ inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,
+ sizeof(ipv4str)),
+ sdl_addr_to_hex(gateway, buf, sizeof(buf)),
+ sdl_addr_to_hex(sender_hw, buf2, sizeof(buf2)),
+ ifp->if_name, ifp->if_unit);
}
- else {
- log(LOG_ERR,
- "arp: %s attempts to modify permanent entry for %s on %s%d\n",
- sdl_addr_to_hex(sender_hw, buf, sizeof(buf)),
- inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,
- sizeof(ipv4str)),
- ifp->if_name, ifp->if_unit);
+ else if (route->rt_expire == 0) {
+ if (log_arp_warnings) {
+ log(LOG_ERR, "arp: %s attempts to modify "
+ "permanent entry for %s on %s%d\n",
+ sdl_addr_to_hex(sender_hw, buf,
+ sizeof(buf)),
+ inet_ntop(AF_INET, &sender_ip->sin_addr,
+ ipv4str, sizeof(ipv4str)),
+ ifp->if_name, ifp->if_unit);
+ }
goto respond;
}
}
-
+
/* Copy the sender hardware address in to the route's gateway address */
gateway->sdl_alen = sender_hw->sdl_alen;
bcopy(CONST_LLADDR(sender_hw), LLADDR(gateway), gateway->sdl_alen);
-
+
/* Update the expire time for the route and clear the reject flag */
- getmicrotime(&timenow);
- if (route->rt_rmx.rmx_expire)
- route->rt_rmx.rmx_expire = timenow.tv_sec + arpt_keep;
+ if (route->rt_expire) {
+ uint64_t timenow;
+
+ timenow = net_uptime();
+ rt_setexpire(route,
+ rt_expiry(route, timenow, arpt_keep));
+ }
route->rt_flags &= ~RTF_REJECT;
-
+
+ /* cache the gateway (sender HW) address */
+ arp_llreach_alloc(route, ifp, LLADDR(gateway), gateway->sdl_alen,
+ (arpop == ARPOP_REPLY));
+
/* update the llinfo, send a queued packet if there is one */
- llinfo = (struct llinfo_arp*)route->rt_llinfo;
+ llinfo = route->rt_llinfo;
llinfo->la_asked = 0;
if (llinfo->la_hold) {
struct mbuf *m0;
m0 = llinfo->la_hold;
- llinfo->la_hold = 0;
-
- /* Should we a reference on the route first? */
- lck_mtx_unlock(rt_mtx);
- dlil_output(ifp, PF_INET, m0, (caddr_t)route, rt_key(route), 0);
- lck_mtx_lock(rt_mtx);
+ llinfo->la_hold = NULL;
+
+ RT_UNLOCK(route);
+ dlil_output(ifp, PF_INET, m0, (caddr_t)route, rt_key(route), 0, NULL);
+ RT_REMREF(route);
+ route = NULL;
}
-
+
respond:
- if (arpop != ARPOP_REQUEST) {
- lck_mtx_unlock(rt_mtx);
- return 0;
+ if (route != NULL) {
+ /* Mark use timestamp if we're going to send a reply */
+ if (arpop == ARPOP_REQUEST && route->rt_llinfo != NULL)
+ arp_llreach_use(route->rt_llinfo);
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
+ route = NULL;
}
-
+
+ if (arpop != ARPOP_REQUEST)
+ goto done;
+
/* If we are not the target, check if we should proxy */
- if (target_ip->sin_addr.s_addr != best_ia->ia_addr.sin_addr.s_addr) {
-
- /* Find a proxy route */
- error = arp_lookup_route(&target_ip->sin_addr, 0, SIN_PROXY, &route);
- if (error || route == NULL) {
-
- /* We don't have a route entry indicating we should use proxy */
- /* If we aren't supposed to proxy all, we are done */
- if (!arp_proxyall) {
- lck_mtx_unlock(rt_mtx);
- return 0;
- }
-
- /* See if we have a route to the target ip before we proxy it */
- route = rtalloc1_locked((const struct sockaddr*)target_ip, 0, 0);
- if (!route) {
- lck_mtx_unlock(rt_mtx);
- return 0;
- }
-
+ if (target_ip->sin_addr.s_addr != best_ia_sin.sin_addr.s_addr) {
+ /*
+ * Find a proxy route; callee holds a reference on the
+ * route and returns with the route entry locked, upon
+ * success.
+ */
+ error = arp_lookup_route(&target_ip->sin_addr, 0, SIN_PROXY,
+ &route, ifp->if_index);
+
+ if (error == 0) {
+ RT_LOCK_ASSERT_HELD(route);
+ /*
+ * Return proxied ARP replies only on the interface
+ * or bridge cluster where this network resides.
+ * Otherwise we may conflict with the host we are
+ * proxying for.
+ */
+ if (route->rt_ifp != ifp &&
+ (route->rt_ifp->if_bridge != ifp->if_bridge ||
+ ifp->if_bridge == NULL)) {
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
+ goto done;
+ }
+ proxied = *SDL(route->rt_gateway);
+ target_hw = &proxied;
+ } else {
+ /*
+ * We don't have a route entry indicating we should
+ * use proxy. If we aren't supposed to proxy all,
+ * we are done.
+ */
+ if (!arp_proxyall)
+ goto done;
+
+ /*
+ * See if we have a route to the target ip before
+ * we proxy it.
+ */
+ route = rtalloc1_scoped((struct sockaddr *)
+ (size_t)target_ip, 0, 0, ifp->if_index);
+ if (!route)
+ goto done;
+
/*
* Don't proxy for hosts already on the same interface.
*/
+ RT_LOCK(route);
if (route->rt_ifp == ifp) {
- rtfree_locked(route);
- lck_mtx_unlock(rt_mtx);
- return 0;
+ RT_UNLOCK(route);
+ rtfree(route);
+ goto done;
}
}
+ /* Mark use timestamp */
+ if (route->rt_llinfo != NULL)
+ arp_llreach_use(route->rt_llinfo);
+ RT_REMREF_LOCKED(route);
+ RT_UNLOCK(route);
}
- lck_mtx_unlock(rt_mtx);
-
- dlil_send_arp(ifp, ARPOP_REPLY, NULL, (const struct sockaddr*)target_ip,
- sender_hw, (const struct sockaddr*)sender_ip);
-
+
+ dlil_send_arp(ifp, ARPOP_REPLY,
+ target_hw, (const struct sockaddr*)target_ip,
+ sender_hw, (const struct sockaddr*)sender_ip, 0);
+
+done:
+ if (best_ia != NULL)
+ IFA_REMREF(&best_ia->ia_ifa);
return 0;
}
void
-arp_ifinit(
- struct ifnet *ifp,
- struct ifaddr *ifa)
+arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
{
+ struct sockaddr *sa;
+
+ IFA_LOCK(ifa);
ifa->ifa_rtrequest = arp_rtrequest;
ifa->ifa_flags |= RTF_CLONING;
- dlil_send_arp(ifp, ARPOP_REQUEST, NULL, ifa->ifa_addr, NULL, ifa->ifa_addr);
+ sa = ifa->ifa_addr;
+ IFA_UNLOCK(ifa);
+ dlil_send_arp(ifp, ARPOP_REQUEST, NULL, sa, NULL, sa, 0);
}
projects / apple / xnu.git / blobdiff